1. Field of the Invention
The present invention relates to a panel assembly, and particularly relates to a panel assembly comprising elongated couplers and upper panels.
2. Description of the Prior Art
In a conventional panel assembly, stringers each having a U-shaped cross section extend in the longitudinal direction of the panel assembly and are disposed at intervals in the transverse direction of the panel assembly, projections and recesses are alternately provided on the top of each of the stringer, and upper and lower panels curved as an arc at both the side edges of the panels extend in the transverse direction of the panel assembly and are engaged with the projections and the recesses so that the panel assembly is constituted as a roof material, as disclosed in the Japanese Patent Publication No. 46-3434. However, it is very troublesome to assemble the panel assembly, because it needs to be assembled as described in the Japanese Patent Publication No. 42-26591.
For that reason, it was conceived that the width of each of the recesses of such stringers are made very small and none of lower panels but upper panels were provided to constitute a conventional panel assembly. However, since the panel assembly has no lower panels, none of the members of the panel assembly closes the gap at the joint of the upper panels located between the stringers. For that reason, the panel assembly cannot be used as a roof material.
Although the conventional panel assembly having the upper and the lower panels prevents a light rain from leaking in through the joints of the upper and the lower panels the panel assembly is likely to fail to prevent a heavy rain from leaking in through the joints.
When each of the conventional panel assemblies is to be used as a roof material, a wall material or a ceiling material and fitted with an advertising sign, an illuminator or the like, support members need to be attached to the panel assembly to fit it with the advertising sign, the illuminator or the like. In order to attach the support members to the panel assembly, it is usually needed that holes are made in the panel of the panel assembly and bolts and nuts are provided. For that reason, not only is it very troublesome to attach the support members to the panel assembly, but also rain is likely to leak in through the holes if the panel assembly is used as a roof material.